JP4810438B2 - Airbag manufacturing method and airbag - Google Patents

Abstract

A method of making an air-bag is disclosed in which a selected plastics material is blow moulded within an appropriate mould to form a blow moulded air-bag. The mould is such that the blow moulded air-bag ( 1 ) has at least one indented region, such as a central oval region ( 10 ) of the upper part ( 7 ) of the air-bag, which, on inflation of the air-bag, becomes outwardly extending.

Description

  The present invention relates to airbags, and more particularly to airbags adapted for use in automobiles to provide protection for automobile occupants.

  It has been conventionally proposed to manufacture airbags from a wide variety of materials. Many airbags are made using a woven material woven from suitable yarns. Such airbags are typically folded and housed in a suitable housing. When the airbag is deployed, the airbag spreads out of the housing. This type of airbag is of particular use as a steering handle airbag or an airbag installed in a front dashboard, as it moves into a free space where it can expand when deployed.

  Other airbags are provided that are installed elsewhere in the vehicle. For example, an airbag may be provided in a cushion of a vehicle seat just in front of the occupant's buttocks sitting on the seat. The airbag is inflated to form a ridge that extends across the front portion of the seat to minimize the risk of "submarining" of a passenger sitting in the seat during the accident. As a variant, the airbag may be installed on the floor of the vehicle in the area of the foot of the occupant sitting on the seat. Such an air bag is inflated to lift an occupant's feet sitting on the seat above the car floor pan during an accident. This minimizes the risk of injury to the feet, ankles and legs of the occupant sitting in the seat due to the deformation of the floor pan that occurs during the accident.

  It has also been proposed to provide a knee airbag in the form of an airbag installed on the backside of an automobile dashboard, which causes the knee of the occupant to move forward and cause knee injury. In order to prevent the vehicle from colliding with the dashboard in such a manner, it is configured to swell into the space between the vehicle dashboard and the vehicle passenger's lap.

  Since airbags are installed in a location where there is no free space available for them to spread, many of these airbags must be made of a material that does not spread when inflated.

  Such airbags often have to withstand harsh conditions, especially floor mounted airbags, which can be rubbed with feet and exposed to a fairly moist environment.

  It has been proposed to make airbags of the type outlined above from a variety of materials including metallic and polymeric materials.

  The present invention seeks to provide an improved manufacturing method of an airbag and an improved airbag.

  According to the present invention, there is a step of blow molding a selected plastic material to form an airbag using a mold that matches the final uninflated state of the airbag, the mold being blow molded A method of manufacturing an airbag is provided, wherein the airbag has at least one recessed area for extending outward when the airbag is inflated.

  Preferably, the method comprises the additional step of providing a gas generator for the airbag.

  Advantageously, the recessed area comprises a recessed groove.

  Preferably, the recessed groove is annular.

  Advantageously, the recessed area comprises a central recessed area.

  Preferably, the plastic contains at least 40% ABS and / or PC.

  More preferably, the plastic contains at least 80% ABS and / or PC.

  In order to make the present invention easier to understand and to understand other features thereof, embodiments of the present invention will be described below by way of example with reference to the accompanying drawings.

  First, referring to FIG. 1, an airbag 1 is shown. The airbag 1 has an integral body that is extruded from a suitable plastic material and then blow molded. Thus, the parison is made by extrusion and the parison is then blow molded.

  Preferred plastic materials include at least acrylonitrile-butadiene-styrene (ABS) or polycarbonate (PC) as a fairly large amount of components. Satisfactory results have been obtained by using a material that is only ABS and a material that is only polycarbonate. In addition, satisfactory results were obtained even when a resin that was a mixture of PC and ABS was used. Also, it is believed that a mixture of polycarbonate and polyethylene terephthalate will prove satisfactory, and therefore preferred materials include at least 40% polycarbonate and / or acrylonitrile-butadiene-styrene. Preferably, the material comprises at least 80% polycarbonate and / or acrylonitrile-butadiene-styrene.

  The selected plastic material is extruded in molten form to form a parison, which is inserted into a suitably shaped mold. Next, the plastic material of the parison is blow-molded in this mold. The mold is shaped to directly manufacture an airbag, such as the airbag 1 shown in FIG. 1, where no further processing of the airbag is required and minimal subsequent processing, for example, a hole leading to a gas generator. Or simple cutting of holes for ventilation may be necessary.

  As can be seen from FIG. 1, the airbag comprises an approximately oval inflatable region 2 and an integral chamber 3 connected to one side of the inflatable region 2 for receiving a gas generator. have. The gas generator to be received in the housing 3 may be of a substantially cylindrical form. The housing 3 has an access hole 4 at one end thereof, and the gas generator is preferably attached at a fixed position through the access hole 4. The gas generator itself may seal the access hole 4, or the access hole 4 may be sealed in some other way.

  The oval inflatable region 2 has a substantially flat shape in the non-inflated state. The portion of the molded product 5 constituting the lower surface of the inflatable region 2 is substantially flat in the orientation shown, but has an inwardly-shaped oval groove, and this groove has an oval inflatable region 2. It is provided at a position slightly spaced from the outer periphery to the inside.

  The part of the molded part that constitutes the upper layer 7 of the inflatable region has an oval channel 8 provided adjacent to the periphery of the inflatable region 2 and recessed directly inward, this channel being inward It is separated from another oval region 10 that is recessed by an upright or outwardly raised ridge 9. The raised portion 9 is collinear with the groove 6.

  The lowermost portion 5 of the inflatable region 2 of FIG. 1 may be placed in place with the positioning against a certain type of support, so that the airbag is deployed. Only the upper part 7 of the inflatable region 2 moves at times.

  When the gas from the gas generator is injected into the interior of the airbag, the inwardly recessed region forming the inwardly recessed groove 8 and the inwardly recessed central oval region 10 is inserted outwardly. It should be understood that it is deformed to be directed. Thus, the airbag is inflated and has the form shown in FIG.

  Accordingly, it should be appreciated that the airbag 1 is blow molded from a selected plastic material and has a configuration with at least one inwardly recessed region. As gas is directed into the interior of the airbag, the inwardly recessed area becomes deformed, thereby allowing the airbag to inflate.

  The airbag of FIGS. 1 and 2 is designed to be used as a side airbag installed on an appropriate part of a vehicle body or as a knee bag installed on the back of a dashboard of an automobile.

  3 and 4 show a modified airbag 20. The airbag 20 has a substantially oval inflatable region 21. The back surface of the inflatable region has an inward channel 22 adjacent to the periphery of the oval region, and a protruding chamber 23 that can accommodate the gas generator and is centrally located.

  The upper portion 24 has an inwardly recessed circumferential groove 25 that surrounds a substantially flat central oval region 26.

  As can be seen from FIG. 4, when the airbag is inflated, the recessed annular groove 25 becomes expanded outwards, and the flat region 24 also bends outwards, thereby fully inflating. Get the air bag.

  Again, this airbag can be used as a side airbag or knee airbag.

  FIGS. 5 and 6 show an alternative embodiment of an airbag 30 which is again formed as a blow molded article of selected plastic material. The airbag 30 is intended to be used as an airbag for diving prevention in an automobile seat.

  This airbag has a substantially rectangular shape. The lower surface 31 of the airbag is provided with a recess 32 at the front edge of the airbag, which is positioned to receive the front lateral beam of the vehicle seat. Another rear recess 33 is provided to receive another lateral beam and the intervening portion 34 of the lower region 31 of the airbag constitutes the chamber.

  The upper surface 36 of the airbag has a substantially flat peripheral region 37. An inwardly oval recess 38 is provided, which surrounds a central formation 39 projecting outward.

  When the airbag is inflated, the recessed channel 38 will extend outwardly, allowing full inflation of the airbag.

  By using a selected plastic material, it is possible to provide an airbag that can withstand harsh conditions and to manufacture the airbag inexpensively and quickly.

  The English terms “comprises” and “comprising” and their derivatives in international publications, when used in the original specification and claims, mean that the specified features, steps or components are included. ing. They should not be construed as excluding the presence of other features, processes, or components.

It is a partial section fragmentary imaginary view of the airbag of the present invention before inflation. FIG. 2 is a view of the airbag of FIG. 1 after inflation. It is a figure corresponding to FIG. 1 which shows another airbag of this invention before inflation. It is a figure which shows the airbag of FIG. 3 after inflation. It is a figure corresponding to FIG. 1 which shows another embodiment of the airbag before inflation. It is a figure of the airbag after inflation.

Claims (9)

A method for manufacturing an airbag, comprising:
Utilizing a mold that matches the final uninflated state of the airbag, and blowing the selected plastic material to form the airbag;
The mold has at least one recessed area for the blown airbag to extend outward when the airbag is inflated ;
The manufacturing method , wherein the plastic includes ABS and PC . The manufacturing method according to claim 1, wherein the plastic contains at least 40% of ABS and PC. The manufacturing method according to claim 2, wherein the plastic contains at least 80% of ABS and PC. Furthermore, the manufacturing method of any one of Claims 1-3 which has the process of preparing the gas generator (4) for the said airbag (1). The manufacturing method according to claim 1 , wherein the recessed region includes a recessed groove (8). The manufacturing method according to claim 5, wherein the groove (8) is annular. The method according to claim 5 or 6, wherein the recessed area includes a central recessed area (10). The manufacturing method according to claim 1, wherein the plastic includes a mixture of ABS and PC.   The airbag (1) manufactured by the method of any one of Claims 1-8.

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